CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical)	12 Months Ended
Dec. 28, 2014	Dec. 29, 2013	Dec. 30, 2012
Treasury Stock, Shares, Acquired	1,594,115us-gaap_TreasuryStockSharesAcquired	580,219us-gaap_TreasuryStockSharesAcquired	454,860us-gaap_TreasuryStockSharesAcquired
Treasury Stock, Shares, Retired	1,559,948us-gaap_TreasuryStockSharesRetired	575,046us-gaap_TreasuryStockSharesRetired	708,996us-gaap_TreasuryStockSharesRetired
Common Class A
Stock Issued During Period, Shares, Employee Stock Purchase Plans	2,391,100	1,030,750	942,250
Stock Issued During Period, Shares, Conversion of Convertible Securities	215,000

Number of shares issued during the period as a result of the conversion of convertible securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-30)

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Number of shares of common and preferred stock retired from treasury during the period.

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